Why Fans on the Golf Course??
OPTIMIZING THE TURFGRASS CANOPY ENVIRONMENT WITH FANS
Fans Can Help Overcome Poor Growing Environments.
Affect On The Health Of Bentgrass Putting Greens
Years of experience have shown that golf superintendents have the most trouble growing bentgrass or Poa annua greens during the summer at a site surrounded by trees or other barriers that allow almost no air movement. A USGA-type green provides a very effective base for growing putting green turf, but it cannot compensate for the lack of air circulation. In this environment, disease and higher rootzone moisture associated with these areas cause turfgrass plants to decline. Fans help improve air flow across greens, and the survival of bentgrass has been shown to improve at sites with the increased air movement provided by fans. The positive effects of fans drying out the soil and increasing evapotranspiration are the two major benefits influencing the bentgrass. Fans offer little cooling benefit to the turfgrass, which is contrary to most popular opinion.
Which Greens Need Fans?
Fans should be specifically used to help improve turf quality at problem green sites. By far the most popular use of fans is at boxed or pocketed sites surrounded by trees or other features that restrict air movement. In the past, these sites have been more prone to summer decline caused by disease, excess moisture, and surface algae. Green sites with wet rootzones also benefit from a fan program. Even small problem areas at open sites can benefit from the use of fans directed to the specific problem area.
Placement Of The Fans
Most superintendents place two stationary fans at the 10 and 2 o’clock positions at the rear of the green, approximately 15 to 30 feet from the edge of the green. Fan height above the green surface normally is 10 feet or less with these stationary fans. Most fan companies sell poles that are usually seven feet tall, since OSHA requires finger guards on any fans positioned at lower heights. Finger guards can restrict air flow distance by up to 12%. Hand guards, which restrict air flow less than finger guards, are required for fans on poles taller than 7 feet. Trees are sometimes used instead of a poles, if available. The key is to position the fan as close to a green and as low to the ground as possible to generate maximum air flow across the green surface. The main goal is to achieve a 3- to 4-mph wind speed over the turfgrass canopy. If fans are too far away or elevated too high, wind speed power will be lost by deflection off the grass itself, or by natural friction loss. Oscillating fans are by far the most popular at golf courses. In the past, fan oscillating motors have caused problems, but today oscillating motors have improved power, similar to the other fan motors. Fan diameters can range from 22 to 48 inches. Because most fans are stationary to poles elevated above the greens, fan diameter size has been increasing with the demand for additional air movement from these products. Many fans now can throw a column of air more than 200 feet. With the improved power of many fans, some air movement can occur even at areas where the fan is not directed.
Fans have made a major impact on many golf courses by helping the turf survive where it previously had died each summer. Many golfers also enjoy the additional comfort of a cool breeze while putting.